The present invention relates to a latent image developing system for producing an image on a substrate, and more particularly, to such a system for producing a multicolor image on a substrate.
One conventional embodiment of a latent image developing system for producing a color image on a substrate comprises a substrate and a dispenser. The substrate is typically paper and has a color developer composition (typically containing organic metallic salts) including a color developer disposed in a latent image on the substrate. The dispenser is adapted to the development of the color image on the substrate by marking thereover and reacting with the color developer composition in the latent image, the dispenser containing a color former composition including a color former. The dispenser is typically a crayon containing wax, the color former and a solvent therefor. This embodiment is well suited to games. The location where the dispenser is to be used may be indicated--e.g., in outline--so that the composition dispensed by the dispenser is not wasted, and the child playing with the game sees an immediate response to his use of the dispenser.
Alternatively, in a carbonless paper embodiment, both the color former and the color developer may be on the substrate, but with one of the color former and color developer contained separately in microcapsules. When pressure is exerted on the microcapsules, e.g., by writing, the microcapsules rupture, whereupon the essentially colorless color former composition comes into contact with the color developer and the desired color marking develops.
The games based on the conventional latent image development systems have not proven to be entirely satisfactory in use. While the limitation of the developed latent image to a single color is perfectly acceptable for carbonless paper, it severely limits the play value of a game as a child will more rapidly lose interest when he is able to predict that movement of the dispenser in a given area will result in a particular color being developed as a result of the color former of the dispenser coming into contact with the color developer of the substrate.
Further, despite the game designer's intention that the child shall apply the color former composition in the dispenser only to particular designated portions of the substrate, children will be children and typically the color former composition in the dispenser is applied willy-nilly over the substrate. Where the developer composition on the substrate has been applied in a particular latent image pattern, the use of the color former composition in the dispenser over the entire surface of the substrate will still only bring out the latent image defined by the presence of the developer composition, but it will waste a substantial amount of the color former composition in the dispenser, which color former composition is typically more expensive than the color developer composition.
Accordingly, it is an object of the present invention to provide a latent image development system for producing a multicolor image on a substrate.
Another object is to provide such a system wherein the color former composition defines the latent image on the substrate and the color developer composition is applied to the latent image on the substrate from a dispenser.
A further object is to provide such a system which is economical to use as the excess application of the composition from the dispenser results in excess application of the cheaper composition.
It is also an object of the present invention to provide such a system which provides greater play value to a game because of the multicolor nature of the developed image.